On this day in 1914, a passenger pigeon named Martha was found dead in the bottom of her cage at the Cincinnati Zoological Gardens. She was 29 years old. She also was the last living member of Ectopistes migratorius, a species that was once perhaps the most prolific bird on the planet. Prior to the European colonization of North America, there was an estimated population of three to five billion passenger pigeons, amounting to 24 to 40 percent of the birds on the continent. Passenger pigeons’ habitat stretched from the Atlantic coast to the Rocky Mountains. The migratory birds traveled in enormous groups that literally darkened the sky for days, according to early explorers’ accounts.

The passenger pigeons needed large forests to feed, and when white settlers began clearing the forests for farming in the 1600s and 1700s, the species gradually turned to eating grain from their fields to survive. Farmers, in turn, shot and poisoned many of the pigeons. But the big blow to the passenger pigeon was the discovery that they tasted good when cooked. Because of their communal lifestyle, passenger pigeons were easy to catch, and starting in the early 1800s, hunters descended upon their gatherings and slaughtered scores of them at a time for sale in city markets, putting burning sulfur pots under trees to daze young birds and cause them to fall from their nests. By the 1850s, the passenger pigeon population was noticeably decreasing, but the pleas of naturalists to slow the killing fell upon deaf ears. One of the last sightings of a great gathering of passenger pigeons occurred in Petosky, Michigan in 1878. Hunters killed an estimated 50,000 birds a day over a five-month period. When the survivors fled and tried to establish a new roost, they were again tracked down and slaughtered, before they could produce any young. By the 1890s, state legislatures finally began to pass laws to protect the passenger pigeon, but by then, so few were left that the species could no longer sustain itself. Today, Martha, whose stuffed remains are part of the Smithsonian collection, is a reminder of how cruelly myopic humans can be. Let’s hope that in this century, she isn’t joined by the last mountain gorilla or white rhino.

And with that sobering warning, here are the science stories of the day.